Internal combustion engine unit and vehicle

Abstract

To provide an internal combustion engine unit and a vehicle capable of early reaching an activation temperature of an exhaust emission control device.SOLUTION: An internal combustion engine unit 2 includes: an internal combustion engine 11; a supercharger 21 that supplies compressed air to the internal combustion engine 11; an intercooler 24 provided between the supercharger 21 and the internal combustion engine 11; a bypass passage 25 provided between the supercharger 21 and the internal combustion engine 11 and bypassing the intercooler 24; a flow control valve 26 that controls a flow rate of the compressed air flowing to the intercooler 24 and the bypass passage 25; and a control section 19 that controls the flow control valve 26 in accordance with an operating state of the internal combustion engine 11 so as to become either operation mode of a first operation mode of causing the compressed air to pass through the bypass passage 25, a second operation mode of causing part of the compressed air to pass through the intercooler 24 and causing the other part of the compressed air to pass through the bypass passage 25 and a third operation mode of causing the compressed air to pass through the intercooler 24.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an internal combustion engine unit having a supercharger and a vehicle. [Background technology]

[0002] For some time now, internal combustion engines have been known that have a supercharger known as a turbocharger to improve fuel economy and thermal efficiency, and a cooler (intercooler) to lower the temperature of the intake air that has passed through the supercharger. Furthermore, as units that use such internal combustion engines, technologies that include an exhaust purification device to suppress the emission of harmful gases, and a system that provides control valves in the exhaust pipe or intake pipe to reduce the amount of intake air are also known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-351184 Summary of the Invention [Problem to be solved by the invention]

[0004] In the internal combustion engine unit described above, the intake air temperature is lowered by a cooler to lower the temperature of the gas pressurized by the turbocharger under all operating conditions. Meanwhile, the fuel injection timing and injection amount are controlled to increase the exhaust temperature of the internal combustion engine so that the temperature reaches the activation temperature of the exhaust gas purification device quickly. However, such control can result in factors such as the time required to reach the activation temperature of the exhaust gas purification device and fuel consumption. While it is conceivable to increase the exhaust gas temperature by reducing the intake air volume by providing a control valve or the like in the exhaust pipe or intake pipe, this configuration also presents the problem of a reduced exhaust flow rate, which prevents the exhaust gas purification device from being sufficiently warmed up.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an internal combustion engine unit and a vehicle that are capable of quickly reaching the activation temperature of an exhaust purification device. [Means for solving the problem]

[0006] According to one aspect of the present invention, an internal combustion engine unit includes: an internal combustion engine; a supercharger that supplies compressed air to the internal combustion engine; an economizer provided between the supercharger and the internal combustion engine; a bypass path that is provided between the supercharger and the internal combustion engine and bypasses the economizer; a flow control valve that controls a flow rate of the compressed air flowing to the economizer and the bypass path; and a control unit that controls the flow control valve according to an operating state of the internal combustion engine so as to switch to one of a first operating mode in which the compressed air is passed through the bypass path, a second operating mode in which a portion of the compressed air is passed through the economizer and another portion of the compressed air is passed through the bypass path, and a third operating mode in which the compressed air is passed through the economizer. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an internal combustion engine unit and a vehicle that can quickly reach the activation temperature of an exhaust purification device. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram that schematically shows the configuration of a vehicle according to an embodiment. [Figure 2] FIG. 2 is an explanatory diagram that schematically shows the configuration of an internal combustion engine unit of a vehicle according to the embodiment. [Figure 3] FIG. 3 is an explanatory diagram showing an example of use of the internal combustion engine unit according to the embodiment. [Figure 4] FIG. 4 is an explanatory diagram showing an example of use of the internal combustion engine unit according to the embodiment. [Figure 5] FIG. 5 is an explanatory diagram showing an example of use of the internal combustion engine unit according to the embodiment. [Figure 6] FIG. 6 is an explanatory diagram showing an example of control of the internal combustion engine unit according to the embodiment. [Figure 7]FIG. 7 is an explanatory diagram showing an example of intake air temperature when the internal combustion engine is under low load in the internal combustion engine unit according to the embodiment and the internal combustion engine unit according to the comparative example. [Figure 8] FIG. 8 is an explanatory diagram showing an example of exhaust gas temperatures when the internal combustion engine is under low load, for an internal combustion engine unit according to the embodiment and an internal combustion engine unit according to a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0009] A vehicle 1 according to one embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG. 1 is an explanatory diagram that schematically shows the configuration of the vehicle 1. FIG. 2 is an explanatory diagram that schematically shows the configuration of an internal combustion engine unit 2 used in the vehicle 1. FIG. 3 is an explanatory diagram that shows an example of use of the internal combustion engine unit 2 when the driving condition is low load, FIG. 4 is an explanatory diagram that shows an example of use of the internal combustion engine unit 2 when the driving condition is medium load, and FIG. 5 is an explanatory diagram that shows an example of use of the internal combustion engine unit 2 when the driving condition is high load. FIG. 6 is a flowchart that shows an example of control of the internal combustion engine unit 2. Note that in each diagram, the configuration is enlarged, reduced, or omitted as appropriate.

[0010] As shown in Figures 1 and 2, the vehicle 1 has an internal combustion engine 11 as a power source, a supercharging system 12, an EGR system 13 that recirculates a portion of the exhaust gas from the internal combustion engine 11, and an aftertreatment device 14 that treats a portion of the exhaust gas from the internal combustion engine 11. The vehicle 1 may be a hybrid electric vehicle (HEV) that is equipped with one or more motors as a power source in addition to the internal combustion engine 11. The vehicle 1 is, for example, a truck. The vehicle 1 is, for example, a flatbed vehicle, a wing vehicle, a covered vehicle, a crane vehicle, an on-board vehicle, a tanker truck, etc. The vehicle 1 is not limited to a truck and may be a bus, a passenger car, a special-purpose vehicle, etc.

[0011] As a specific example, the vehicle 1 includes an internal combustion engine 11, a supercharging system 12, an EGR system 13, an aftertreatment device 14, an intake air temperature sensor 15, an accelerator opening sensor 16, an engine speed sensor 17, a memory unit 18, and a control unit 19. The vehicle 1 also includes a chassis 20 having a drive shaft, an automatic transmission, a power transmission device, four or more wheels, a cabin, a battery, a cooling fan including a heat exchanger, etc. The internal combustion engine 11, the supercharging system 12, the EGR system 13, the aftertreatment device 14, and the intake air temperature sensor 15 constitute an internal combustion engine unit 2.

[0012] The internal combustion engine 11 is, for example, a diesel engine. In the following description, the "internal combustion engine" may also be referred to as the "engine." The internal combustion engine 11 is, for example, a multi-cylinder engine having a plurality of combustion chambers 11a. The internal combustion engine 11 is connected to a fuel tank. The internal combustion engine 11 is supplied with fuel from the fuel tank and operates to generate power (torque) that serves as driving force. The internal combustion engine 11 is equipped with an intake manifold 11b that introduces air into each combustion chamber 11a, and an exhaust pipe 11c that joins and exhausts burned gases from each combustion chamber 11a.

[0013] The supercharging system 12 includes a compressor 21, an air cleaner 22, an intake pipe 23, an intercooler 24, a bypass path 25, and a flow control valve 26.

[0014] The compressor 21 is a supercharger. The compressor 21 compresses air and supplies it to the internal combustion engine 11. The compressor 21 is driven, for example, by the output of the internal combustion engine 11. As a specific example, the compressor 21 is connected via a rotating shaft to a turbine 27 provided downstream of the internal combustion engine 11, for example, in the exhaust pipe 11c, and is driven by the rotation of the turbine 27. Note that the compressor 21 may have a motor as a drive source in addition to the turbine 27, or may not have the turbine 27 and be driven by a motor.

[0015] The air cleaner 22 filters the outside air drawn in by the compressor 21 .

[0016] The intake pipe 23 fluidly connects the compressor 21 and the intake manifold 11 b of the internal combustion engine 11 .

[0017] The intercooler 24 is a so-called intercooler. The intercooler 24 is provided between the compressor 21 and the internal combustion engine 11. The intercooler 24 is provided in the intake pipe 23. The compressed air that is discharged from the compressor 21 and moves to the internal combustion engine 11 passes through the intercooler 24, thereby cooling the compressed air. That is, the intercooler 24 lowers the intake air temperature of the internal combustion engine 11.

[0018] The bypass path 25 is formed by, for example, piping or the like. The bypass path 25 bypasses the economizer 24. The bypass path 25 is connected to the intake pipe 23 on the upstream side (primary side) of the economizer 24, which is the compressor 21 side, and on the downstream side (secondary side) of the economizer 24, which is the internal combustion engine 11 side. The bypass path 25 supplies the compressed air supplied from the compressor 21 to the internal combustion engine 11 without passing through the economizer 24, bypassing the economizer 24.

[0019] The flow rate control valve 26 is provided at a branch point of the intake pipe 23 between a flow path to the economizer 24 and a flow path to the bypass path 25. The flow rate control valve 26 is a solenoid valve capable of controlling the flow rate of compressed air flowing into the economizer 24 and the bypass path 25. For example, the flow rate control valve 26 is configured to be able to control the flow rate of compressed air in two directions, such as to be able to flow the compressed air only into the economizer 24, only into the bypass path 25, or to both the economizer 24 and the bypass path 25. The flow rate control valve 26 is also configured to be able to control the flow rate of compressed air flowing into both the economizer 24 and the bypass path 25. The flow rate control valve 26 is connected to the control unit 19, and is a solenoid valve capable of adjusting the flow rate to the economizer 24 and the bypass path 25 by controlling the opening degree of an internal valve with the control unit 19.

[0020] The EGR system 13 is a system that recirculates EGR gas, which is part of the exhaust gas from the internal combustion engine 11, and mixes it with intake air to reduce the amount of oxygen in the intake air and lower the combustion temperature in the combustion chamber of the internal combustion engine 11, thereby reducing NOx in the exhaust gas. The EGR system 13 includes an EGR pipe 31, an EGR cooler 32, and an EGR valve 33. The EGR system 13 also includes a supply device that supplies a cooling medium, such as cooling water or outside air, to the EGR cooler 32.

[0021] The EGR pipe 31 is a pipe that constitutes an EGR flow path. The EGR pipe 31 is connected to the exhaust pipe 11c on the exhaust side of the internal combustion engine 11 on the secondary side of the junction and to the intake manifold 11b of the internal combustion engine 11 on the primary side of the branching portion.

[0022] The EGR cooler 32 is provided in the EGR pipe 31. The EGR cooler 32 is provided on the EGR flow path formed by the EGR pipe 31, and EGR gas passes through the inside of the EGR cooler 32.

[0023] The EGR valve 33 is a flow control valve that controls the flow rate of the recirculated exhaust gas by controlling the opening degree. The EGR valve 33 is an electromagnetic valve that is connected to the control unit 19 and can control the flow rate of the exhaust gas flowing to the EGR cooler 32 by controlling the opening degree of an internal valve.

[0024] The aftertreatment device 14 is an exhaust purification device that processes exhaust gas and reduces harmful substances contained in the exhaust gas, such as SOF (Soluble Organic Fraction), particulate matter, and NOx. The aftertreatment device 14 is provided, for example, in the exhaust pipe 11c, and is equipped with aftertreatment devices such as a supplementary catalyst and filter for reducing SOF (Soluble Organic Fraction), particulate matter, and NOx in the exhaust gas from the internal combustion engine 11, and a urea SCR (Exhaust Gas Recirculation) system.

[0025] The intake air temperature sensor 15 detects the temperature of the mixture of intake air and EGR gas, and outputs a signal corresponding to the detected temperature to the control unit 19. The intake air temperature sensor 15 is provided, for example, at a branching portion of the intake manifold 11b.

[0026] The accelerator opening sensor 16 detects the opening of the accelerator and outputs a signal corresponding to the opening to the control unit 19. The accelerator opening sensor 16 is a position sensor that detects the position of the accelerator.

[0027] The rotation speed sensor 17 detects the rotation speed (engine rotation speed) of the internal combustion engine 11, and outputs a signal corresponding to the detected rotation speed to the control unit 19.

[0028] The memory unit 18 is a storage medium. The memory unit 18 is a memory device, such as a read-only memory (ROM), a random access memory (RAM), a hard disk drive (HDD), a solid state drive (SSD), or an integrated circuit storage device, that stores various data. The memory unit 18 may be physically implemented as a single memory device or as multiple physically separated memory devices. The memory unit 18 stores various control setting values ​​and various control programs for controlling the vehicle 1. The memory unit 18 also stores information detected by various sensors, including the intake air temperature sensor 15, the accelerator position sensor 16, and the engine speed sensor 17. The memory unit 18 stores data such as programs and thresholds for determining the load of the internal combustion engine 11 corresponding to the accelerator position and engine speed. For example, the memory unit 18 stores programs and data that can determine three loads of the internal combustion engine 11: low load, medium load, and high load. The storage unit 18 also stores a program and various data for controlling the opening of the flow control valve 26 in an operation mode corresponding to each load.

[0029] The control unit 19 is a computing device. The control unit 19 is, for example, an ECU (Electronic Control Unit). The control unit 19 controls at least one of various electrical components, such as chassis control, motor control, headlight control, air conditioning system control, fuel injection control, brake system control, lane keeping system control, inter-vehicle distance control system control, and car navigation system control. Various sensors, including an intake air temperature sensor 15, an accelerator position sensor 16, and an engine speed sensor 17, are connected to the control unit 19, and output signals from these sensors are input to the control unit 19. The control unit 19 determines the load of the internal combustion engine 11 based on the operating conditions of the internal combustion engine 11, such as the fuel injection amount calculated from the accelerator position acquired from the accelerator position sensor 16 and the engine speed of the internal combustion engine 11 acquired from the engine speed sensor 17, and performs intake control to control the opening of a flow control valve 26 according to the load of the internal combustion engine 11. Here, as the intake control, the control unit 19 controls the aperture of the flow rate control valve 26 so as to select one of the following operation modes: a first operation mode in which the compressed air is passed through the bypass path 25; a second operation mode in which part of the compressed air is passed through the intercooler 24 and another part of the compressed air is passed through the bypass path 25; and a third operation mode in which the compressed air is passed through the intercooler 24.

[0030] The control unit 19 includes, for example, a software configuration including a load determination unit that determines the load on the internal combustion engine 11 and an opening control unit that controls the opening of the flow control valve 26 for intake control. The load determination unit determines whether the load on the internal combustion engine 11 is low, medium, or high based on the accelerator opening and engine speed obtained from the accelerator opening sensor 16 and the engine speed sensor 17. As an example, the load determination unit of the control unit 19 calculates a fuel injection amount from the accelerator opening and engine speed obtained from the accelerator opening sensor 16 and the engine speed sensor 17, and determines whether the load on the internal combustion engine 11 is low, medium, or high based on the calculated fuel injection amount. Here, the relationship between the fuel injection amount and the load on the internal combustion engine 11 is such that a large fuel injection amount indicates a high load, and a small fuel injection amount indicates a low load.

[0031] For this reason, for example, three ranges are set from the minimum value to the maximum value of the fuel injection amount injected in the internal combustion engine 11 of the vehicle 1, and the three ranges of the fuel injection amount can be set in advance as threshold values ​​corresponding to low load, medium load, and high load of the internal combustion engine 11, respectively, and stored in the memory unit 18. As a specific example, if the range on the minimum side of the three ranges of the fuel injection amount is defined as a low range, the range on the maximum side of the fuel injection amount is defined as a high range, and the range between the low range and the high range is defined as a middle range, the low range of the fuel injection amount corresponds to a low load of the internal combustion engine 11, the middle range of the fuel injection amount corresponds to a medium load of the internal combustion engine 11, and the high range of the fuel injection amount corresponds to a high load of the internal combustion engine 11.

[0032] The load determination unit then compares the determined fuel injection amount with a threshold value, and can determine the load of the internal combustion engine 11 from the load corresponding to the range of the determined fuel injection amount among the three ranges of the fuel injection amount. Note that the differences between the upper and lower limit values ​​of each of the three ranges of the fuel injection amount may be the same value or may be different values.

[0033] The opening control unit controls the opening of the flow control valve 26 in accordance with the load of the internal combustion engine 11 determined by the load determination unit, and controls the flow rate of the compressed air from the compressor 21 passing through the intercooler 24 and the bypass path 25. As a specific example, when the internal combustion engine 11 is under low load, the opening control unit controls the opening of the flow control valve 26 in a first operation mode, and causes the compressed air to pass only through the bypass path 25. In other words, when the internal combustion engine 11 is under low load, the opening control unit causes the entire flow rate of the compressed air to pass through the flow control valve 26 so as to flow through the bypass path 25.

[0034] When the internal combustion engine 11 is under a medium load, the opening control unit controls the opening of the flow control valve 26 as a second operation mode to pass compressed air through both the economizer 24 and the bypass path 25. Furthermore, when the internal combustion engine 11 is under a medium load, for example, the opening control unit controls the flow rates of the compressed air through the economizer 24 and the bypass path 25 based on the temperature of the mixed gas detected by the intake air temperature sensor 15. For example, when the internal combustion engine 11 is under a medium load, if the temperature of the mixed gas detected by the intake air temperature sensor 15 is higher than a predetermined temperature, the opening control unit makes the flow rate of the compressed air passing through the economizer 24 larger than the flow rate of the compressed air passing through the bypass path 25, and if the temperature of the mixed gas detected by the intake air temperature sensor 15 is lower than the predetermined temperature, the opening control unit makes the flow rate of the compressed air passing through the economizer 24 smaller than the flow rate of the compressed air passing through the bypass path 25. Here, the predetermined temperature is a temperature that is set in advance and stored in the memory unit 18. Furthermore, the predetermined temperature is, for example, the activation temperature of components such as the catalyst of the aftertreatment device 14, and is set based on, for example, the temperature of the exhaust gas from the internal combustion engine 11, i.e., the temperature at which the exhaust gas temperature at the inlet of the aftertreatment device 14 can reach the activation temperature of the aftertreatment device 14.

[0035] When the internal combustion engine 11 is under high load, the opening control unit controls the opening of the flow rate control valve 26 in the third operation mode to pass the compressed air only through the intercooler 24. In other words, when the internal combustion engine 11 is under high load, the opening control unit passes the compressed air through the flow rate control valve 26 so that the entire flow rate of the compressed air flows through the intercooler 24.

[0036] In this way, the opening control unit controls the opening degree of the flow control valve 26 so that the temperature of the mixed gas of intake air and EGR gas detected by the intake air temperature sensor 15 becomes a desired temperature. Note that when the internal combustion engine 11 is under a low load or a high load, the opening control unit may cause the compressed air to flow to both the bypass path 25 and the economizer 24 based on the temperature of the mixed gas detected by the intake air temperature sensor 15, rather than causing the compressed air to flow only to the bypass path 25 or only to the economizer 24. In this case, it is preferable to increase the opening degree of the flow control valve 26 so that the flow rate of the compressed air flowing through the bypass path 25 or the economizer 24 is larger than that in the case of a medium load. Furthermore, when the internal combustion engine 11 is under a medium load, the opening control unit may open the flow control valve 26 at a preset opening degree stored in the memory unit 18, and cause the compressed air to flow to the economizer 24 and the bypass path 25 at a predetermined flow rate ratio.

[0037] Next, an example of a method for controlling the EGR system 13 of the vehicle 1 configured as above will be described with reference to the explanatory diagrams of FIGS. 3 to 5 showing an example of the flow of compressed air and the flow chart of FIG.

[0038] As shown in FIG. 6, first, in step ST1, while the vehicle 1 is traveling, the control unit 19 determines the operating conditions of the vehicle 1. Here, the operating conditions of the vehicle 1 are the load on the internal combustion engine 11. For example, the control unit 19 calculates a fuel injection amount from the accelerator opening and engine speed acquired from the accelerator opening sensor 16 and engine speed sensor 17, and determines the load on the internal combustion engine 11 as low load, medium load, or high load based on this fuel injection amount and a threshold value stored in the memory unit 18. For example, the control unit 19 determines that the internal combustion engine 11 is under low load if the fuel injection amount calculated from the accelerator opening and engine speed is in the low range, determines that the internal combustion engine 11 is under medium load if the fuel injection amount calculated from the accelerator opening and engine speed is in the middle range, and determines that the internal combustion engine 11 is under high load if the fuel injection amount calculated from the accelerator opening and engine speed is in the high range.

[0039] 3 , when it is determined that the operating state of the internal combustion engine 11 is low load, the control unit 19 controls the flow control valve 26 in the first operation mode to cause the entire flow rate of compressed air to flow through the bypass path 25. Note that the control unit 19 may monitor, for example, the temperature of the mixed gas acquired by the intake air temperature sensor 15, and when the temperature of the intake air temperature sensor 15 is higher than a predetermined temperature stored in the memory unit 18 even when the load is low, cause part of the compressed air to flow through the economizer 24, and at this time, may variably control the flow rate of the mixed gas flowing through the economizer 24 and the bypass path 25 in accordance with the temperature of the mixed gas.

[0040] 4 , the control unit 19 controls the flow control valve 26 in the second operation mode to cause compressed air to flow through both the intercooler 24 and the bypass path 25. At this time, the control unit 19 monitors, for example, the temperature of the mixed gas acquired by the intake air temperature sensor 15, and controls the aperture of the flow control valve 26 to control the flow rate of the compressed air passing through the intercooler 24 so that the temperature of the mixed gas becomes a predetermined temperature stored in the memory unit 18.

[0041] When it is determined in step ST4 that the operating condition of the internal combustion engine 11 is high load, the control unit 19 controls the flow control valve 26 in the third operation mode as shown in Fig. 5 to cause the entire flow rate of compressed air to flow to the intercooler 24. Note that the control unit 19 may monitor, for example, the temperature of the mixed gas acquired by the intake air temperature sensor 15, and when the temperature of the intake air temperature sensor 15 is lower than a predetermined temperature stored in the memory unit 18 even when the load is high, cause part of the compressed air to flow to the intercooler 24, and at this time, may variably control the flow rates of the mixed gas flowing through the intercooler 24 and the bypass path 25 in accordance with the temperature of the mixed gas. Furthermore, the control unit 19 monitors the operating conditions when the vehicle 1 is being driven, and controls the flow control valve 26 based on the determined load.

[0042] With the internal combustion engine unit 2 and vehicle 1 configured as described above, for example, when the internal combustion engine is operating at a low load or a medium load, the intake and exhaust gas temperatures of the internal combustion engine 11 can be improved by passing part or all of the compressed air through the bypass path 25. For example, FIG. 7 shows an example of the gas temperature (intake temperature) at the inlet of the internal combustion engine 11 in a vehicle not having the bypass path 25 of the comparative example, and the gas temperature (intake temperature) at the inlet of the internal combustion engine 11 when the entire flow rate of compressed air passes through the bypass path 25 in the vehicle 1 having the bypass path 25 of the embodiment. Similarly, FIG. 8 shows an example of the gas temperature (exhaust temperature) at the inlet of the aftertreatment device 14 in a vehicle not having the bypass path 25 of the comparative example, and the gas temperature (exhaust temperature) at the inlet of the aftertreatment device 14 when the entire flow rate of compressed air passes through the bypass path 25 in the vehicle 1 having the bypass path 25 of the embodiment. As shown in FIGS. 7 and 8 , when the internal combustion engine unit 2 supplies compressed air to the internal combustion engine 11 by flowing the compressed air through the bypass path 25, the gas temperatures of the intake air and exhaust air of the internal combustion engine 11 can be made higher than when the air passes through the intercooler 24.

[0043] Generally, as the gas temperature increases, the gas density decreases, and therefore, torque and output decrease when combustion occurs in the combustion chamber 11a. Conversely, as the gas temperature decreases, the gas density increases, and torque and output increase. Therefore, as in the present embodiment, by providing a bypass path 25 that bypasses the intercooler 24 downstream of the compressor 21, which is a turbocharger, and controlling the flow rates of the intercooler 24 and the bypass path 25, the vehicle 1 can suppress the generation of excess torque and output and reduce fuel consumption by introducing intake air (compressed air) into the internal combustion engine 11 without cooling it in a low load range of the internal combustion engine 11. Furthermore, when the internal combustion engine 11 is under a medium load, the intake air can be controlled to a predetermined temperature by passing part of the compressed air through the intercooler 24 to cool it and passing the other part of the compressed air through the bypass path 25 without cooling it. Therefore, the vehicle 1 can suppress harmful substances contained in exhaust when combustion occurs in the combustion chamber 11a while maintaining suitable torque and output. Furthermore, when the internal combustion engine 11 is under high load, all of the compressed air is passed through the intercooler 24 to be sufficiently cooled before being introduced into the internal combustion engine 11, thereby ensuring high torque and high output.

[0044] Furthermore, the internal combustion engine unit 2 can increase the intake temperature by passing some or all of the compressed air from the compressor 21 through the bypass path 25, so that the intake temperature increases as shown in Fig. 7, and the exhaust temperature also increases accordingly, as shown in Fig. 8. Therefore, the internal combustion engine unit 2 can increase the exhaust temperature without having to reduce the amount of exhaust and intake gas by providing a separate control valve or the like, and can therefore reach the activation temperature of the aftertreatment device 14, which is an exhaust purification device, earlier than the vehicle 1 of the comparative example that does not have the bypass path 25.

[0045] As described above, according to the internal combustion engine unit 2 and the vehicle 1 according to the embodiment, the flow rates of the compressed air flowing through the intercooler 24 and the bypass path 25 are controlled in accordance with the load on the internal combustion engine 11, so that the activation temperature of the aftertreatment device 14 can be reached quickly.

[0046] The present invention is not limited to the above-described embodiment. For example, in the above example, three operating conditions of the internal combustion engine 11, namely, low load, medium load, and high load, have been described as examples of operating conditions of the internal combustion engine 11 for the control unit 19 to control the flow control valve 26. However, the present invention is not limited to these. The operating conditions of the internal combustion engine 11 may be two or more, and it is sufficient that the flow rates of the compressed air flowing through the intercooler 24 and the bypass path 25 can be controlled in accordance with each operating condition. Furthermore, the example in which the control unit 19 controls the flow control valve 26 based on the operating conditions of the internal combustion engine 11 has been described, but the present invention is not limited to these. For example, the control unit 19 may correct the operating conditions and the opening degree of the flow control valve 26 using an outside air temperature detected by an outside air temperature sensor provided in the vehicle 1 or an intake air flow rate / mass sensor provided upstream of the compressor 21 as a correction value.

[0047] In the above example, the aftertreatment device 14 is described as an example of an exhaust purification device having a catalyst or filter for reducing SOF (Soluble Organic Fraction), particulate matter, and NOx, a urea SCR (Exhaust Gas Recirculation) system, etc. However, the exhaust purification device is not limited to this. The exhaust purification device can be appropriately set as long as it has an activation temperature set within the temperature range of the exhaust from the internal combustion engine 11 and can purify harmful substances in the exhaust.

[0048] 7 and 8, the gas temperature at the inlet of the internal combustion engine 11 (i.e., the intake air temperature of the internal combustion engine 11) and the gas temperature at the inlet of the aftertreatment device 14 (i.e., the exhaust temperature of the internal combustion engine 11) can be controlled by the opening degree of the flow control valve 26. Therefore, in the above example, the control unit 19 controls the opening degree of the flow control valve 26 using the intake air temperature sensor 15 provided in the intake manifold 11b on the inlet side of the internal combustion engine 11, but this is not limiting. For example, the temperature sensor 15 may be a temperature sensor that detects the temperature of the exhaust gas of the internal combustion engine 11, i.e., the temperature of the gas at the inlet of the aftertreatment device 14, and the control unit 19 may control the opening degree of the flow control valve 26 based on this temperature sensor 15.

[0049] The present invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the embodiments may be implemented in appropriate combinations, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combining selected elements from the disclosed elements. For example, if the problem can be solved and the desired effect can be obtained even if some elements are deleted from all elements shown in the embodiments, the configuration from which these elements are deleted can be extracted as an invention. [Explanation of symbols]

[0050] 1...vehicle, 11...internal combustion engine, 11a...combustion chamber, 11b...intake manifold, 11c...exhaust pipe, 12...supercharging system, 13...EGR system, 14...aftertreatment device, 15...intake air temperature sensor (temperature sensor), 16...accelerator opening sensor, 17...rotation speed sensor, 18...memory unit, 19...control unit, 20...chassis, 21...compressor (supercharger), 22...air cleaner, 23...intake pipe, 24...intercooler, 25...bypass path, 26...flow control valve, 27...turbine, 31...EGR pipe, 32...EGR cooler, 33...EGR valve

Claims

1. an internal combustion engine; a supercharger that supplies compressed air to the internal combustion engine; an intercooler provided between the turbocharger and the internal combustion engine; a bypass path provided between the turbocharger and the internal combustion engine and bypassing the intercooler; a flow control valve that controls a flow rate of the compressed air flowing into the intercooler and the bypass path; a control unit that controls the flow rate control valve according to an operating state of the internal combustion engine so as to switch the operation mode to one of a first operation mode in which the compressed air is passed through the bypass path, a second operation mode in which a portion of the compressed air is passed through the economizer and another portion of the compressed air is passed through the bypass path, and a third operation mode in which the compressed air is passed through the economizer; An internal combustion engine unit comprising:

2. an EGR system that recirculates a portion of the exhaust gas of the internal combustion engine as intake air for the internal combustion engine and mixes it with the compressed air; an exhaust purification device that treats exhaust from the internal combustion engine; a temperature sensor for detecting the temperature of the intake air or the exhaust air, 2. The internal combustion engine unit according to claim 1, wherein the control unit controls the opening degree of the flow control valve based on the temperature detected by the temperature sensor when in the second operating mode.

3. An accelerator opening sensor; a rotation speed sensor for the internal combustion engine, The internal combustion engine unit according to claim 1 , wherein the control unit determines the operating condition based on an accelerator opening degree and an engine speed obtained from the accelerator opening degree sensor and the engine speed sensor.

4. A vehicle comprising an internal combustion engine unit according to any one of claims 1 to 3.

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